Interlocked clearing mechanism



United States Patent Inventors Dietmar Hummel,

Schwenningen, and Wilhelm Haupt, Villlngen, Germany App]. No. 818,204 Filed April 21, 1969 Patented Dec. 8, 1970 Assignee Kienzle Apparate GmbH,

Villingen, Germany Priority April 20, 1968 Germany No. 1,774,147

INTERLOCKED CLEARING MECHANISM 18 Claims, 9 Drawing Figs.

US. Cl. 222/33; 235/144 Int. Cl. B67d 5/26 Field of Search..... 235/144(D1sp.),

61(M), 94(Cursory); 222/33, 34,. i 35 References Cited UNITED STATES PATENTS Carroll Hazard Pilz et al. Stasenko Robinson et al.

Primary ExaminerStephen .l. Tomsky Attorney-Michael S. Striker ABSTRACT: In order to prevent starting of the pump motor of a service station during the clearing of the volume counter, a control member is shifted between a blocking position blocking rotation of clearing control means, but permitting opening and closing of the pump motor switch, and a locking position sliding on the rotary clearing control means and locking the switch in the open position so that the pump motor cannot be started during clearing of the counter. Additional interlock means for preventing operations leading to errors are provided.

PATENTEDHEB ,arsm 3545549 sum 1 or 7 INVE NTORS Dietmur l-iummel et al PATENIEUDEC 8|97U 35451649 sum 2 or T INVENTORS Dielmur Hummel el al PATENTEUBEB 8197B 3545549 SHEEI 3 OF 7 INVE NTORS Dietmur Hummel et al PATENTEDBEB 8l976 3545649 SHEET t UF 7 INVENTORS Dietmar Hummel e! 1| 1 INTERLOCKED CLEARING MECHANISM BACKGROUND OF THE INVENTION The invention relates to an interlocked clearing mechanism for use with a counter provided in price calculating apparatus of a gasoline station under consideration of the function of switch means by which the pump motor for the dispensed gasoline is controlled.

lnterlocked clearing mechanism is not only intended for facilitating the operation of gas stations, and to carry out the required operations in the shortest possible time, but should also provide complete safety against wrong operations. Basic conditions are that before each dispensing operation,.the volume counter and price counter number wheels must be cleared and returned to the zero position, before the pump motor starts to pump gasoline, and that after the dispensing of the gasoline, return of the discharged nozzle to its cradle effects the stopping of the pump motor.

Apparatus of this type'is known in which the discharge nozzle resting on a cradle controls a slide to which the clearing spring is connected. When the discharge nozzle is returned to the cradle, the weight of the discharge nozzle tensions the clearing spring, while the removal of the discharge nozzle from the cradle starts the clearing operation at whose ends end the slide closes the switchof the pump motor. While the operation of this clearing mechanism is .very simple, there is no interlock which permits the start of a clearing operation only after the clearing spring has been completely tensioned.

Under such circumstances,.it may happen that the clearing operation is only partly carried out, whereupon the switch' of the pump motor is closed, and dispensing of gasoline starts. The indicationof the counter is wrong since it does not start with zero.

Another clearing mechanism disclosed in the US. Pat. No. 2,874,875 provides a manually operated lever nearthe cradle of the discharge nozzle which can be turned inone direction for tensioning the clearing spring, and in the opposite direction for starting the'clearing operation which is-followed by the actuation of the motor switch. The operator is compelled by the particular arrangement of the lever to perform the-several operations in a predetermined sequence since the cradle for the discharge nozzle is covered after the same has been removed. Only when the manually operatedlever is fully placed in its initial position, assuring that the clearing spring is completely tensioned and wound up, the discharge nozzle can be placed again on its cradle after completion of the dispensing of the desired volume of fluid. Although this construction assures a complete clearing during the following dispensing operation, there is the disadvantage that the tensioning of the clearing spring, the start of the clearing operation, and finally the start of the pump motor must be manually initiated. Only after all these manually started functions, the discharge of gasoline into the tank of a car can begin-with a substantial loss of time. Furthermore, the construction is not entirely foolproof and requires attention of the operator.

Another clearing mechanism is disclosed in the German Pat. No. 1,251,063, and provides a turnable spring loaded operating member which is locked by two locking levers during and at the end of the tensioning of the clearing spring against the action of the same. A starting member, controlled by the discharge nozzle, acts on the locking levers when the same engage the respective locking members. In one direction of movement the starting member effects a clearing operation, and in the other direction of movement, it effects the disconnection of the pump motor; This arrangement has also disadvantages inasmuch as the clearing control disc which controls the clearing operation, also controls the start and cutting off of the pump motor. In some constructions, erroneous operation during the dispensing of gasoline, causes a running of the clearing control disc to a position in which the drive couplings for the price register and volume register are disengaged, while the pump motor is still operating, resulting in dispensing SUMMARY OF THE INVENTION It is one object of the invention to overcome the disadvantages of known clearing mechanisms for counters of service stations, and to provide an interlocked clearing mechanism of comparatively simple construction which prevents erroneous operations and is fully controlled by removal and return of a discharge nozzle.

It is another object of the invention that upon manual removal of the discharged nozzle, a series of automatic operations take place during which gasoline is dispensed in the tank of a car, whereupon return of thedischarge nozzle to its cradle prepares the mechanism for the next operation.

Another object of the invention is to provide an interlocked clearing mechanism which is completely automatic and does not permit any erroneous operation.

To accomplish these objects, the following conditions are preferably present:

1. The clearing control means can be arrested only in a position in which the clearing spring is fully tensioned.

2. The start of the clearing operation, and the release of the clearing control means for rotation, must be possible only if the clearing spring is completely tensioned, that is stores sufficient energy for a complete clearing operation.

3. In the wound-up position of the clearing control means, it must be possible to start the clearing operation in a simple manner requiring little manual force.

4. Only after the completed clearing operation, a switch of the pump motor must be automatically placed in the closed position for starting the pump motor.

5; Additional interlocks must be provided which prevent the closing of the'pump motor switch before the termination of the entire clearing operation by clearing means.

6. There should be no possibility of interrupting the clearing operation intentionally or unintentionally.

7. The initiation of the clearing operation, and the opening of the pump motor switch should be controlled by a single manually operated element, such as the discharge nozzle.

With these objects in view,the present invention relates to a mechanism for controlling the clearing of the number wheels of a counter indicating the volume or price of dispensed gasoline making use of the switch of the pump motor. The energy for the clearing operation is supplied by a spring which is wound up before the clearing of the counter either by a shaft of the counter or by manual operation, for example by the placing of a discharge nozzle on its cradle at the end of a gasolinedispensing operation. In accordance with the invention, the start of the pump motor depends on the completion of the clearing operation effected by an operating member driven by the clearing spring and driving a clearing control means through a pinion and a one-way clutch.

In accordance with the invention, the clearing control means is a circular clearing member which has an axially projecting control rim cooperating with a control member which has a blocking position preventing the clearing operation by engaging a cutout in the control rim, and being movable to a locking position in which the switch controlling the pump motor is locked in an open position. During the clearing operation, the control member in the locking position slides on the control rim, and after the clearing operation, the control member falls into a cutout of the control rim, assumes the blocking position, and permits the movement of the motor switch to a position in which the pump motor pumps gasoline.

It is an advantage of the invention that all functions required for the clearing operation, and also the switching of the pump motor, are effected by the control rim of a single rotary clearing member which has two cutouts spaced from each other and cooperating with the control member. Since the control rim is provided on the rotary clearing member, and forms a single means with the same, which is connected for movement with the spring loaded operating member, and since the clearing member drives the two control slides of the counter, the entire control is effected by a single means.

As compared with the prior art, the mechanism of the invention requires only few parts, and linkages provided in prior art apparatus for controlling the motor switch, for example, can be omitted. As a result, the reliability of the functions does not depend on the tolerances of so many parts so that the mechanism is not prone to disturbances, and the possibilities of wrong operations are reduced to a minimum.

An embodiment of the invention comprises switch means having open and closed positions and controlling the pump motor; a spring motor including an operating member and clearing spring means for turning the operating member in a driving direction; windup means for turning the operating member in a windup direction for tensioning the clearing spring means; rotary clearing control means for operating the clearing means of the counter for dispensed fluid, and including a circular clearing member connected with the operating member for rotation and turned by the same in a clearing direction when the same turns in the driving direction, and a control rim having at least one, and preferably'two diametrically spaced cutouts; a control member having a locking position for locking the switch means in the open position and a blocking position blocking movement of the clearing control means in the clearing direction by engaging a cutout in the rim, and releasing the switch means for movement to the closed position; and manually operated means, preferably including the cradle of the discharge nozzle, and other members, movable in one direction for moving the control member to the locking position and the switch means to the open posi tion, and movable in the opposite direction for moving the switch means to the closed position after the control member in said blocking position has blocked movement of the clearing control means in the clearing direction at the end of the clearing operation.

Due to this interlock, no clearing can take place when the switchmeans is closed, and the pump motor cannot operate while the clearing control means effects clearing of the counter. i

In one embodiment of the invention, the windup means include a drive cam rotated for one revolution by the counter during the gasoline dispensing operation. In another embodiment, the manually controlled means, such as the cradle of the discharged nozzle, is connected by a windup coupling with the operating member so that the clearing spring means is manually wound up.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary perspective view illustrating a first embodiment of the invention in a normal waiting position between dispensing operations in which the spring motor is wound up, the motor switch open, and a clearing operation blocked;

FIG. 2 is a side elevation illustrating on an enlarged scale, the embodiment of FIG. 1 in a position assumed by the mechanism after a clearing operation;

FIG. 3 is a side elevation illustrating the embodiment of FIG. 1 in a wound-up position in which the motor switch is open, and clearing starts;

FIG. 4 is a side view of a part of the embodiment of FIGS. 1 to 3;

FIGS. 5 and 6 illustrate two operational positions of an interlock device of the embodiment of FIG. 1;

FIG. 7 is a fragmentary perspective view illustrating another embodiment of the invention in a normal waiting position between dispensing operations;

FIG. 8 is a side elevation illustrating on an enlarged scale the embodiment of FIG. 7 in a position assumed by the mechanism after clearing operation, and corresponding to the position of FIG. 2; and

FIG. 9 is a side elevation illustrating on an enlarged scale the embodiment of FIG. 7 in a position wound-up by a counter shaft during the dispensing of fluid, corresponding to FIG. 3, so that clearing can start.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The ordinal sets of number wheels 1 have shafts 4 mounted in bearings carried by a pair of supporting walls 2 and 3 between which number wheels 1 are disposed. Support wall 3 carries the clearing means and a control mechanism for the same, and the support wall 2 carries a price calculator, not shown, which does not form part of the present invention.

The clearing mechanism includes a circular clearing member 7 and a pinion 8 mounted on a stud shaft 12 for rotation, a coupling member 8a secured to pinion 8 and cooperating with two spring-loaded coupling pawls 16 carried on pivot pins on clearing member 7, and connecting pinion 8 with clearing member 7 for rotation in clockwise direction. Pinion 8 meshes with a gear segment 9 of an operating member 5 which has an arm 11 to which a spring 10 is attached for biassing operating member 5 to turn in counterclockwise direction. Operating member 5 has ratchet teeth 14 cooperating with a ratchet pawl 15 biassed by spring 55 to turn about a pivot 54 into a position engaging one of the coupling teeth 16. Clearing member 7 has two abutments 17 which, at the end of a clearing operation when gear segment 9 has turned with operating member 5 in counterclockwise direction, abut an abutment portion 18 of operating member 5 to limit rotation of clearing member 7, as shown in FIG. 2.

The rear face of clearing member 7, which confronts wall 3, has two cam portions, cooperating with two can follower members, respectively, of which one cam follower member 25 is located between clearing member 7 and wall 3, while the other cam follower member, not shown, is located behind wall 3. Cam follower member 25 has four arms 25a having recesses for receiving the ends of crank arms 27 which are fixed on shafts 28 extending between the walls 3 and 2 and carrying a series of clearing arms 29 cooperating with clearing heart cams, not shown, which are respectively secured to the number wheels la. The other cam follower member, not shown, also has four arms which are operatively connected with drive bails and control the coupling and disengagement, and other functions during, before, and after the clearing operation.

Clearing member 7 has a peripheral axially projecting control rim 19 which is interrupted by two diametrically arranged cutouts 20. A control member 22 is mounted for turning movement about a pivot 24 on wall 3 and carries a pin 31 cooperating with a cutout in the end portion of a lever 30, and a blocking portion 23 whose surface 23a cooperates with the end faces of the rim portions 19 for blocking turning movement of clearing member 7. Control member 22 has a control surface 23b cooperating with the arm 36 of an angular lever 35 which is mounted for turning movement in wall 3 and connected by a dog clutch 37 with a switching shaft 38 by which the motor switch 39 is actuated. The free end of lever 35 is pivotally connected with a link 62 which is pivotally connected with a lever 59 mounted on a pivot 58 and carrying a roller 57. A spring 61 biasses link 62 and lever 59.

FIG. 3 illustrates the mechanism in a wound-up condition, and it is assumed that the operator of the service station has just placed the discharge nozzle, not shown, on its rest so that operating member 5 has been turned in clockwise direction from the position of FIG. 2 to the position of FIG. 3 so that clearing spring 10 is tensioned.

Lever 30, which in the position of FIG. 2 was turned by spring 40 to abut stop 41 on operating member 5, has been turned to a position abutting pin 31 of control member 22 whose blocking surface 23a abuts the other peripheral surface of control rim 19. i

A lever 42 is mounted on a shaft 12 and has a coupling projection 43, a control arm .44, and a curved arm with a curved slot 45 into which a pin 64 projects. When lever 42 turns in counterclockwise direction, pivot 46 and [ever 30 are displaced so that control member 22 is turned to an actuating position and displaces link 33 with the camr'ning guide way 33a which moves along theguide pin 34 and turns link 33 about pivot 32.

A torsion wire spring 53 is mounted on a stud on ratchet pawl and engages a stud 52 on link 33. A coupling pawl 48 is mounted on a pivot 50 carried by portion 13 of operating member 5, which also carries a spring 49 abutting a stud on operating member 5, and another stud on coupling pawl 48 so that the same is biassed to turn toward coupling projection 43. Link 33 has an abutment stud 56 cooperating with a abutment projection 26 on cam follower member 25a.

When lever 42 is turned, and control member 22 is turned in the direction of the arrow in FIG. 3, link 33 performs a composite motion due to the camming guide way 33a, and initiates three operations:

1. Coupling pawl 48 is turned by stud 51 of link 33 about pivot 50 and disengaged from coupling projection 43 of lever 42;

2. Stud 52 of link 33 acts on spring 53 to move ratchet pawl 15 to a position disengaged from ratchet teeth 14 on portion 13 of operating member 5; and

3. Abutment stud 56 is placed by link 33 in a position located opposite abutment 26 of cam followermember 25 which has started movement toward the clearing position in which clearing arms 29 cooperate with the heart cams, not shown.

As best seen in FIG. 3, control arm 44 of lever 42, which turns in counterclockwise direction, makes roller 57 on double-arm lever 59 free for movement under the action of spring 61 toward cam portions 63..Lever 59 transmits motion through link 62 to angular lever 35 and thereby to the switching shaft 38 of motor switch 39.

After the start of the clearing operation, spring 10 drives the mechanism to perform the clearing operation. Operating member 5 turns in counterclockwise direction so that the cam portions 63 cooperate with roller 57. In the meantime, a stud 60 on cam follower member 25 which is driven by operating member 5 through segment gear 9, pinion 8, coupling 80, and clearing member 7, is in its lowermost operative position so that stud 60 is positioned adjacent the projection 59a of lever 59 and locks the same until clearing arms 29, cooperating with the heart cams, not shown, have completed the clearing operation of the number wheels 12:.

After stud 60 has returned to its initial position, a blocking portion 23 of control lever 22 has engaged a cutout 20, the operating member 5 has run down under the action the spring 10 so that roller 57 is located in the cam recess of arm 13 of operating member 5, and coupling pawl 48 operated by stud 51 has engaged coupling projection 43 of lever 42, lever 35 operates switching shaft 38 to disconnect motor switch 39 under the action of spring 61 The dog clutch 47 which is connected with lever 42, is connected by a linkage, not shown, with the supporting cradle of a discharge nozzle so that placing of the discharge nozzle on its cradle effects turning of clutch 47 and thereby of lever 42 in clockwise direction, while removal of the discharged nozzle from its cradle by the operator of'the service station, effects a turning of lever 42 in counterclockwise direction.

After an amount of gasoline has been dispensed through the discharged nozzle, the operator places the discharge nozzle on its cradle so that a linkage transmits the movement of the depressed cradle to the clutch 47 to turn the same with lever 42 in clockwise direction. FIG. 2 shows the initial position of lever 42. Coupling pawl 48 engages the coupling projection 43 of lever 42 so that upon turning of lever 42, operating member 5 is also turned in clockwise direction so that its arm 11 tensions and winds up clearing spring 10. At the same time, cam portion 63 of operating member 5 displaces follower roller 57 with follower lever 59 so that link 62 is shifted, and lever 35 turns switching shaft 38 to disconnect motor switch 39 so that the motor, not shown, by which the pump, not shown, is driven is stopped.

During the winding up of the clearing spring 10, ratchet pawl 15 successively engages the notches and teeth 14 of operating member 5 to block turning movement of the same under the action of the clearing spring 10. At the same time,

.the torsion spring 53 which forms an extension of ratchet pawl 15 resiliently engages stud 52 to hold link 33 with control member 22 in the blocking position in which blocking surface 23a abuts the end face of control rim 19 of clearing member During the angular displacement of operating member 5 in clockwise direction for winding up spring 10, pinion 8 with coupling part 8a are driven in counterclockwise direction, but due to the fact that coupling 8a, 16 is a one-way coupling, this rotary motion is not transmitted toclearing member 7.

At the end of the winding up operation, the two coupling pawls 16 engage coupling part 80, and the last ratchet tooth 14 has passed ratchet pawl 15 which until this moment has blocked a return rotation of operating member 5 due to the action of the tensioned clearing spring. A sufficient distance between the last ratchet tooth 14 and the point of ratchet pawl 15 permits a frictionless withdrawal of ratchet pawl 15 to the position of FIG. 3 when link 33 is shifted, and its stud 52 displaces spring extension 53 with ratchet pawl 15.

When operating member 5 has arrived in the angular position shown in FIG. 3, the respective abutment 17 on clearing member 7 is already released by abutment portion 18 of operating member 5, and lever 30 can engage stud 31 of control lever 22 since at the end of the wind-up movement, the stop stud 41 on arm 11 of operating member 5 has released lever 30 due to the turning movement transmitted from shaft 12 to lever 42.

As explained above, clearing spring 10 was tensioned due to the placement of the discharged nozzle, not shown, on its cradle whereby operating member 5 is turned to its wound end position in which the mechanism is in the position shown in FIG. 1. In this position, lever 42 is angularly displaced so that stop pin 64 engages the other end of slot 45, while roller 57 is located in a curved recess below control arm 44 of lever 42 and blocked by the same against movement under the action of spring 61 biassing lever 59 on which roller 57 is mounted.

The mechanism is ready for the next clearing operation which is started when the operator of the service station, removes the discharge nozzle from its cradle, which is moved up by a spring, not shown, and transmits this motion through a linkage, not shown, to the clutch 47 so that lever 42 is turned in counterclockwise direction until the other end of slot 45 engages stop pin 64. Control arm 44 releases roller 57 which is urged against a peripheral cam portion 63 by spring 61, as shown in FIG. 3. The angular displacement of lever 42 is transmitted by lever 30 to stud 31 so that control lever 22 is turned in clockwise direction to the position of FIG. 3 in which blocking portion 23 releases the end face of control rim 19, and abuts the outer peripheral surface of control rim 19 when the clearing member 7 turns in clockwise direction.

The angular displacement of control lever 22 results in three operations.

The stud 51 is displaced with link 33 and turns coupling pawl 48 to a position releasing coupling projection 43 of lever 42, and holds coupling pawl 48 in this disengaged position during the entire clearing operation. At the same time, the locking projection at the lower end of coupling pawl 48 is displaced to the position shown in FIG. 5 for blocking movement of roller 57 into the cam recess 63. Stud 52 on link 33 displaces spring 53 with ratchet pawl 15 to release the ratchet teeth 14 of operating member 5, as shown in FIG. 3. At the moment of the start of the clearing operation, there is no pressure on ratchet pawl 15, since the last ratchet tooth 14 in the wound-up position of operating member and spring is withdrawn in circumferential direction from the point of ratchet pawl 15.

During displacement of link 33, the camming guide way 330 moves along guide pin 34 so that the free end of link 33 is transversely displaced until abutment stud 56 is transversely displaced to a position located before the arresting abutment 26 whereby link 33 is locked and prevented from moving back to its initial position before the clearing operation has been completed. Since link 33 and control member 22 are locked during the clearing operation, control member 22 cannot operate lever 35 to close motor switch 39 and start the pump motor before the clearing of the number wheels 1a of counters 1 is completed.

If the motor were started too early before the clearing is completed, the volume of the dispensed liquid still represented by the partly clearedvnumber wheels la, would be added to the volume dispensed during the following dispensing operation so that the respective customer would have to pay an incorrect amount.

The clearing spring 10, acting on arm 11, now turns the operating member in counterclockwise direction. This motion is transmitted by gear segment 9, pinion 8, and one-way coupling 8a, 16, to the clearing member 7. After the same has turned exactly 180 in clockwise direction, while control rim 19 of clearing member 7 holds control member 22 in the position shown in FIG. 3, blocking portion 23 can again fall into a cutout and block turning movement of clearing member 7, while control surface 23b of blocking portion 23 releases the angular arm 36 of lever 35 so that spring 61, acting on link 62, urges lever 35 to the position shown in FIG. 2 in which motor switch 39 starts the pump motor. The cam portion 63 of operating member 5 permits the actuation of motor switch 39 only after operating member 5 has arrived in the end position of FIG. 2 in which the roller 57 falls into the cam recess 63, permitting the angular displacement of lever 59 by spring 61 required for operation of link 62, lever 35, and motor switch 39.

A further interlock preventing premature start of the pump motor is obtained by the locking projection 59a of lever 59 which abuts abutment pin 600i cam follower member until the same is in a position corresponding to the complete clearing of the number wheels In by the arm 29 acting on the clearing heart cams, not shown.

If an attempt is made to displace lever 42 out of the position assumed upon start of the clearing operation, such displacement cannot interrupt or stop the automatic clearing operation of the mechanism.

As shown in FIG. 5, displacement of lever 42 positions coupling portion 43 opposite the coupling portion of coupling pawl 48 so that the same cannot assume its coupling position, and locking portion 95 blocks movement of roller 57 with lever 59 into cam recess 63. Only if lever 42 is in its correct end position, in which stop pin 64 abuts the left end of slot 45 after turning of lever 42 in counterclockwise direction, can coupling pawl 48 be moved by spring 49 to the coupling position engaging coupling projection 43 so that roller 57 can fall into cam recess 63 of operation member 5, as shown in FIGS. 2 and 6, so that motor switch 39 is operated to start the pump motor. As is apparent from FIG. 6, the next following windup operation of the clearing mechanism is already prepared in this position, so that return of the discharge nozzle to its cradle will start the winding up of the clearing mechanism.

It must be prevented that disturbing manipulations of the operator can influence, or even interrupt, the clearing operation. For this purpose, the arm 11 of operating member 5 has the stop 41 which turns lever to a position in which it cannot cooperate with stud 31 of control member 22, as shown in FIG. 2. Only after dispensing of gasoline has been completed, and the discharge nozzle has been placed again on its cradle,

resulting in complete tensioning of clearing spring 10, stud 41 releases lever 30 so that the same is moved by spring 40 to a position in which its cutout free end is located under stud 31 so that the mechanism isready for the next dispensing operation.

While in the embodiment of FIGS. 1 to 6, a manual operation is required for providing the force for winding up the spring 10 of the clearing mechanism, the modified embodiment illustrated in FIGS. 7, 8 and 9 provides a drive 6 which is coupled with the counter at the beginning of the dispensing operation, and provides the force for tensioning the clearing spring.

Parts of the embodiment of FIGS. 7, 8 and 9 which correspond to the parts of the mechanism described with reference to FIGS. 1 to 3, function in the same manner, and therefore need not be described further. In accordance with the modified construction of FIGS. 7, 8 and 9, the operating member 5 has an arm 70 carrying on a pivot 71 a roller 69 which cooperates with a rotary cam 65 of the drive 6. Cam 65 is mounted for free rotation on a shaft 66 and has a projection 68 and an end stop 67. A projection 73 of operating member 5' moves projection 68 out of a position coupled with a drive of the counter, and an arm 72 of operating member 5 cooperates with stop 67 in the position of FIG. 9. The lower end of operation member 5 carries a locking member 75 on a pair of guide pins 76 which project into slots of locking member 75. A spring 77 is connected to a stud 78 on locking member 75 and to one of the pins for holding locking member 75 in the illustrated position.

A shaft 86 is mounted in wall 3 and in a bearing bracket 85, and carries a lever 87 having an end portion 87a cooperating with a pin 83 on a lever 79 which is mounted on a pivot 82 which is secured to wall 3. Pivot 82 also forms a stop for limiting angular movement of lever 87 in one direction, while lever 87 is stopped in the other direction by its projection 87b when the same engages bearing bracket 85. A coupling pin 89 and a guide pin 88 are also mounted on lever 87.

A spring 91 is secured to a stud on lever 87 and to another stud 92 on a link 93 and biasses the same to turn in clockwise direction toward the coupling pin 89. A connecting link 62 is connected by a pivot with one end of lever 79 whose other end supports a roller 80 on a pin 81. A spring 61 is secured to link 62 and to wall 3 and biasses link 62 downward, for turning lever 79 to a position abutting a stop 60 on cam follower member 25 which is controlled by cams on the rear face of clearing member 7, as described above. Roller 80 cooperates with a curved portion of locking member 75 in the position of FIG. 9, and can fall into a cam recess 74 of operating member 5.

When the discharge nozzle is removed from its cradle, the counter l is cleared whereupon operating member 5' assumes the position shown in FIG. 8. The abutment 17 on the clearing member 7, and the abutment portion 18 of operating member 5' are in locking engagement in the cleared position of the counter, and, after a turning of clearing member 7 for exactly determine the position of the cutout 20 of the control rim 19 so that the controllever 22 can engage an end face of control rim 19 with blocking surface 23a. At the same time, roller 69 of arm 70 of operating member 5', is lowered to the rising lobe of cam 65, and stop arm 72 has released stop 67 on cam 65 so that coupling projection 68 is permitted by the retracted abutment 73 to couple with the drive shaft of the counter.

Control lever 22 releases arm 36 of lever 35 so that the pump motor is started by switch 39.

The dispensing operation starts, and cam 65, which is coupled with counterll, rotates in clockwise direction and acts on follower roller 69 to turn operating member 5' also in clockwise direction about shaft 12. After turning of cam 65 about an angle of 350, the follower roller 69 is on the highest portion of the cam lobe, and the clearing spring 10 is fully wound up and tensioned, while operating member 5 assumes the position of FIG. 7. During turning of operating member 5',

gear segment 9, with pinion 8 and coupling part 8a, is turned an angle of 180 in counterclockwise direction without turning clearing member 7 since the one-way clutch 8a, 16 is disengaged until coupling part 8a has been turned 180 whereupon it is engaged by the coupling-pawl l6. Cam 65 completes one revolution and is disconnected from the drive shaft of the counter due to the action of projection 73 on projection 68 of a clutch whereupon cam 65 is arrested by arm 72 engaging stop 67. I

The roller 80 on lever 79 which during the winding up operation fell into recess 74, has turned locking member 75 to a position in which spring 77 is tensioned. After completion of thedispensing operation, the discharge nozzle is again placed on its cradle which, in a known manner, is operatively connected with shaft 86 so that shaft 86 turns with lever 87 in counterclockwise direction. The end portion 87a of lever 87 engages pin 83 on lever 79, and turns the same in counterclockwise direction whereby link 62 is shifted and operates through lever 35 and coupling 38, motor switch 39 to stop the pump motor. Due to the angular displacement of lever 79 about pivot 82, 'roller 80' has released locking member 75 which turns under the action of spring 77 and prevents roller 80 from falling into recess 74 so that an operation of link 62 for starting the motor is prevented.

The link'93, which is released by stop 41 due to the turning movement of operating member on which stop 41 is mounted, can now be moved by spring 91 to the position of FIGS. 7 and 9 in which its cutout end portion engages coupling pin 89 at the end of the angular displacement transmitted from the cradle of the discharge nozzle to shaft 86 and lever 87. In the position of the mechanism shown in FIG. 7, the mechanism is ready for the next dispensing operation which starts with the removal of the discharge nozzle from its cradle which causes the mechanism to assume the position shown in FIG. 9.

When the empty cradle moves up due to the action of the spring, not shown, shaft 86 is turned through a conventional linkage, not shown, in clockwise direction with lever 87. Couplingpin 89 moves with lever 87 and displaces link 93 so that control lever22' is turned out of the blocking position shown in FIG. 8 to the position of FIG. 9, releasing the control rim 19 of clearing member 7. The tensioned spring acts through operating member 5', gear segment 9, pinion 8, and the engaged one-way clutch 8, 8a, on clearing member 7 which is turned in clockwise direction. As explained above, control member 23 locks lever 35 and prevents the start of the pump motor by operation of motor switch 39 until clearing member 7 has turned 180, and control member 23 engages the other cutout in rim 19. Locking member 75 prevents roller 80 of lever 79 to drop into the recess 74 in operating member 5 before the clearing operation is completed, and constitutes a second interlock preventing premature actuation of motor switch 39 and start of the pump motor. Roller 80 of lever 79 is urged by spring 61 acting on link 62 to engage the curved periphery of locking member 75, and is released by the same only after operating member 5' has completed its turning movement under the action of clearing spring l0,'whereupon locking member 75 is in a position in which it does not interfere with the movement of lever 79 with roller 80, as shown in FIG. 8. During the final phase of the clearing operation, stop 60 on cam follower member 25 which controls the heart cam clearing operation, is engaged by lever 79 whereby a third interlock is provided for preventing for stopping of the pump motor before the completion of the clearing operation. Only after cam follower member25 has reached the position in which arms 29 have turned the heart cams to the position in which the number wheels 1a are cleared, lever 79 can turn far enough for closing motor switch 39 by displacement of lever 79 with link 62. Due to the. turning of operating member 5 about shaft 12 during the clearing operation, link 93 is moved by stud 41 out of engagement with coupling pin 89 so that during the clearing operation, any improper manual turning of shaft 86 with lever 87 has no influence on link 93 so that control member 22 and switch 39cannot be manipulated in a fraudulent manner.

SUMMARY As is apparent from the above above-detailed description of the preferred embodiments, a clearing mechanism according to the invention comprises switch means 35 to 39 controlling the pump motor, clearing means 25 to 29 for the counter 1, an operating member 5 or 5', clearing spring means 10 for turning the operating member 5 in a counterclockwise driving direction, windup means for turning operating member 5 in a clockwise winding direction for tensioning the spring means and including in the embodiment of FIGS. 1 to 3 a tensioning member 42 to 45 and a spring loaded coupling 48 which couples tensioning member 42 to 45 with operating member. 5, and in the embodiment of FIGS. 7 to 9, drive cam 65, shaft 66, and coupling means 68, 73, a rotary clearing control means including clearing member 7 and control rim 9 having cams, not shown, for operating clearing means 25 to 29, and heart cams respectively connected with the number wheels 1a, and connected by a one-way clutch 8a, 16 and by a pinion 8 to operating member 5 so that clearing control means 7, 19 turns in a clockwise clearing direction when operating member 5 turns in the counterclockwise driving direction, a control member 22 having a locking position shown in FIGS. and 9 for locking switch means 35 to 39 in the open position, and being biassed by springs 53 or 91 to move to a blocking position shown in FIGS. 2 and 8 blocking movement of the clearing control means 7, 9 in the clockwise clearing direction and releasing switch means'35 to 39 for movement to the closed position shown in FIGS. 2' and 8, and manually operated means including the discharge nozzle, not shown, and member 47 connected to tensioning members 42 to 45, or in the embodiment of FIGS. 7 to 9, shaft 86 and arm 87.

Spring biassed means including a link 62 and a cam follower 59 or 79 are connected with switch means 35 to 39 and urge the same due to the action of spring 61 to the closed position. Operating member 5 or 5' has a cam portion 63 or 74 cooperating with the respective cam follower for blocking operation of the switch means during rotation of the operating member 5 until the respective camfollower roller falls into a cam recess at the time control member 22 moves into one of the cutouts 20.

An interlock link 33 is connected with control member 22 and has means 33a cooperating with the fixed pin 34 for guiding link 33 to a position engaging the clearing means 25, 26 with an abutment 56. The interlock link 33 also operates ratchet pawl 15 and coupling 48. The stop 60 on cam follower member 25a of the clearing means, blocks movement of cam follower 59 and shifting of the switch means 35 to 39 by the spring biassed means 59, 62, 61 until the clearing operation is completed by the clearing means 25 to 29, and the heart cam.

Links 30 or 93 are operated by the manually operated tensioning member 42 or by the manually operated arm 87 to shift at the proper moment, control member 22 from the blocking position shown in FIGS. 1 or 7 to the locking position shown in FIGS. 3 and 9.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of clearing apparatus for counters differing from the types described above.

While the invention has been illustrated and described as embodied in a clearing mechanism for preventing start of a pump motor during clearing of a counter counting the volume of the pumped and dispensed fluid, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

We claim:

1. In a fluid dispensing apparatus including a pump motor, and a counter for dispensed fluid, in combination an interlocked clearing mechanism comprising switch means having open and closed positions and controlling said pump motor; clearing means for said counter; an operating member mounted for angular movement; clearing spring means for turning said operating member in a driving direction; windup means for turning said. operating member in a windup direction for tensioning said clearing spring means; rotary clearing control means for operating said clearing means connected with said operating member and turned by the same in a clearing direction when the same turns in said driving direction, a control member having a locking position for locking said switch means in said open position, and being biassed to a blocking position blocking movement of said clearing control means in said clearing position direction and releasing said switch means for movement to said closed position;and manually operated means movable in one direction for moving said control member'to said locking position and said switch means to said open position, and movable in the opposite direction for moving said switch means to said closed position after said control member in said blocking position has blocked movement of said clearing control means in said clearing direction at the end of a clearing operation so that no clearing can take place while said switch means is closed and so that said pump motor cannot operate while said clearing control means effects clearing of said counter.

2. Clearing mechanism as claimed in claim 1 wherein said clearing control means includes a rotary clearing member and a peripheral control rim onsaid clearing member having at least one cutout forming an abutment face on said control rim; and wherein saidcontrol member in said blocking position is located in said cutout engaging said abutment face, and slides in said locking position on said peripheral control rim while said clearing control means is rotated in said clearing direction by said operating member due to the action of said clearing spring means,

3. Clearing mechanism is claimed in claim 1 comprising spring biassed means connected with said switch means and urging the same to said closed position, said spring biassed means'including a cam follower; and wherein said operating member has a cam portion cooperating with said cam follower for blocking operation of said switch means by said spring biassed means during rotation of said operating member in said driving direction until said control member moves to said blocking position blocking said clearing control means.

4. Clearing mechanism as claimed in claim 3 wherein said switch means includes a motor switch, and a lever connected with said switch and cooperating with said control member; and wherein said spring biassed means include a link connected with said lever and articulated to said cam follower, and a spring for biassing said link to turn said lever to close said switch and for biassing said cam follower toward said cam portion.

5. Clearing mechanism as claimed in claim 1 comprising an interlock link pivotally connected with said control member and having means for guiding said interlock link to a longitudinally and transversely displaced position while said control member moves to said locking position, said interlock link in said displaced position engaging said clearing means and being locked by the same against longitudinal movement with said control member so that the latter cannot move out of said locking position before completion of the clearing operation by said clearing means.

6. Clearing mechanism as claimed in claim 1 wherein said manually operated means include a tumable tensioning member; wherein said windup means include a spring biassed coupling connecting said tensioning member with said operating member for turning movement in said windup direction;

- and comprising a biassed ratchet pawl for engaging notches in said operating member in successive positions during movement in said windup direction so as to prevent movement of said operating member in said driving direction.

7.=Clearing mechanism ascl a imed in claim 6 comprising an interlock link pivotally connected with said control member for movement therewith, and operating said ratchet pawl to release the engaged notch when said control member is in said locking position. I t

8. Clearing mechanism as claimed in claim 7 wherein said ratchet pawl includes a spring portion engaged by said interlock link so that spring portion is bent by said interlock link when said ratchet pawl engages said notches.

9. Clearing mechanism as claimed in claim 6 comprising an interlock link pivotally connected with said control member for movement therewith, and operating said spring biassed coupling to disconnect'said tensioning member from said operating member when said control member is in said locking position so that saidoperating member cannot be turned in said windup direction.

10. Clearing mechanism as claimed in claim 1 comprising an interlock link pivotally connected with said control member and having means for guiding said interlock link to a longitudinally and transversely displaced position while said control member moves to said locking position, said interlock link in said displaced position engaging said clearing means and being locked by thesame against longitudinal movement with said control member so that the latter cannot move out of said locking position before completion of the clearing operation by said clearing means; wherein said manually operated means include a tumable tensioning-member; wherein said windup means include a spring biassed coupling connecting said tensioning member with said operating member for turning movement in said windup direction; and comprising a biassed ratchet pawl for engaging notches in said operating member in successive positions during movement in said windup direction so as to prevent movement of said operating member in said driving direction; said interlock link operating said ratchet pawl to release the engaged notch when said control member is in said locking position, and operating said spring biassed coupling to disconnect said tensioning from said operating member when said control member is in said locking position so that said operating member cannot be turned in said windup direction.

ll. Clearing mechanism as claimed in claim 1 wherein said clearing control means includes a clearing member and a circular peripheral control rim on said clearing member formed with two diametrically opposite cutouts bounded by abutment faces respectively engaged by said control member in said blocking position for blocking movement of said clearing control means in said clearing direction; wherein said operating member has a plurality of ratchet teeth and notches; comprising a ratchet pawl biassed to successively engage said notches during turning of said operating member in said windup direction for blocking movement in said driving direction; comprising a one-way clutch connecting said clearing control means with said operating member, said clutch including a clutch member connected with said operating member for rotation, and two clutch pawls mounted on said clearing member diametrically spaced from each other and engaging said clutch member in two positions during rotation in said clearing direction, said clutch pawls and said ratchet pawl being disposed so that said clutch pawls engage said clutch member at the moment in which said ratchet pawl is circumferentially spaced from the last ratchet tooth and said control member registers with one of said cutouts, and comprising an interlock link connected with said control member for movement therewith and moving in .said locking position of the same said ratchet pawl out of engagement with said ratchet teeth while said ratchet pawl circumferentially spaced from said last ratchet tooth and no pressure is exerted by said last ratchet tooth on said ratchet pawl.

12. Clearing mechanism as claimed in claim 1 wherein said manually operated means include a tensioning member, and a link mounted on said tensioning member for angular movement between an operative position registering with said control member and an inoperative position; comprising a stop on said operating member, and a spring connecting said operating member with said link and urging said link to abut said stop in said inoperative position after turning of said operating member in said driving direction to an end position in which said clearing control means is blocked by said control member in said blocking position after a clearing operation; wherein said windup means include a spring biassed coupling connecting said tensioning member with said operating member so that turning of said tensioning member with said operating member in said windup direction moves said link to said operative position and consequent turning of said member in said driving direction operates said link to move said control member from said blocking position to said locking position so that rotation of said clearing control means in said clearing direction starts.

13. Clearing mechanism as claimed in claim 1 comprising spring biassed means connected with said switch means and urging the same to said closed position, said spring biassed means including a cam follower; wherein said operating member has a cam portion cooperating with said cam follower forblocking operation of said switch means by said spring biassed means during rotation of said operating member in said driving direction until said control member moves to said blocking position blocking said clearing control means; wherein said clearing means has a stop; and wherein said cam follower means has a projection cooperating with said stop so as to block movement of said spring biassed means so that said switch means cannot be moved to said closed position before said clearing means has cleared said counter.

14. Clearing mechanism as claimed in claim 1 comprising spring biassed means connected with said switch means and urging the same to said closed position, said spring biassed means including a cam follower; wherein said operating member has a cam portion cooperating with said cam follower for blocking operation of said switch means by said spring biassed means during rotation of said operating member in said driving direction until said control member moves to said blocking position blocking said clearing. control means; wherein said manually operated means include a turnable tensioning member; wherein said windup means include a spring biassed coupling member turnably mounted on said operating member and biassed to engage said tensioning member for coupling said'operating member with said tensioning member, said coupling member having a blocking portion cooperating with said cam follower and blocking movement of said spring biassed means, and of said switch means to said closed position when said manually operated means and said tensioning member are operated during a clearing operation.

15. Clearing mechanism as claimed in claim 1 wherein said windup means include a drive cam; coupling means for connecting said drive cam with said counter during the dispensing of fluid by said pump motor in said closed position of said switch means; and wherein said operating member has means for engaging said coupling for one revolution of said drive cam, and a cam follower portion cooperating with said drive cam.

16. Clearing mechanism as claimed in claim 1 comprising spring biassed means biassed for moving said switch means to said closed position, and including a cam follower and a cam follower roller thereon; comprising a spring biassed locking member mounted on said operating member and cooperating with said cam follower roller; wherein said operating member has a cam portion including a cam recess cooperating with said cam follower roller so that when said cam follower roller is released by said locking member, said cam follower roller can move into said cam recess whereby said spring biassed means move said switch means to said closed position when said operating member has moved to an end position in which said clearing control means is blocked by said control member in said blocking position after a clearing operation so that said locking member moves with said operating member during the entire clearing operation.

17. Clearing mechanism as claimed in claim 1 wherein said manually operated means include an arm tumable in opposite directions; comprising a link connected with said switch means, a cam follower articulated to said link, and a spring acting on said link to move said switch means to said closed position; wherein said arm engages and displaces said cam follower during movement in one direction for moving said switch means to said open position; and comprising a locking member movably mounted on said operating member and cooperating with said cam follower for holding the same and thereby said switch means in said open position.

18. Clearing mechanism as claimed in claim 17 comprising a coupling pin on said arm; a link articulated to said control member and having a free end cooperating with said coupling pin; a spring connecting said arm with said free end and urging the same to a position engaging said coupling pin during movement of said arm in said one direction so that movement of said arm thereafter in a direction opposite to said one direction moves said control member from said blocking position to said locking position; said spring biassing said control member toward said blocking position. 

